Friday, August 24, 2012

Great year for prairie dock

This has turned out to be a great year for prairie dock (Silphium terebinthenaceum), which is interesting considering the continuing drought. All our prairie dock sites are very lush, and the flower stalks are quite tall.

Prairie dock flower stalk towers over this 6 ft 3 inch person.

At Pleasant Valley Conservancy we have very lush plants in the Barn, Crane, Pocket, Ridge, and Valley prairies, all of which have been planted. We also have tall flowering stalks in both Toby's Prairie and our Unit 11A savanna, neither of which we planted.

But this isn't all. The most impressive stand of prairie dock is the railroad prairie between Cross Plains and Black Earth (on U.S. 14 just west of where County KP goes north). This site has always had native prairie dock, but there is more this year than there has ever been. In fact, there is so much that invading wild parsnip has been suppressed. (I have been told that this prairie was one of the first remnants that Curtis and Greene studied, way back in the late 1940s.)

Even this isn't all. There are two prairie dock patches that are hardly ever seen but are flourishing this year along the south side of U.S. 14 beteen Stagecoach Road and Twin Valley Road.

Why is this drought year so good for prairie dock? As is well known, this species is very deep rooted, up to 14 feet deep (according to some reports). Thus, moisture should not be a problem. However, this does not explain why it has run amok. I'm guessing that the unusually warm weather this summer has had something to do with it. (How many days have we had with temperatures above 90 F? Lots.)

Although it takes quite a few years for prairie dock to become established (our plants first flowered in the 5th or 6th years after planting), once firmly in place they are long lived.